Abstract: One or more polymeric hollow fiber membranes are pyrolyzed to form one or more hollow fiber CMS membranes by directing a flow of pyrolysis gas through a polymeric membrane cartridge (including a porous center tube around which one or more green, polymeric, hollow fiber membranes is arranged) or a bundle of polymeric membranes (including a plurality of green, polymeric hollow fiber membranes oriented so that their ends are disposed with ends of the bundle) in a direction perpendicular to a length direction of the cartridge or bundle in order to sweep away off-gases that are formed during pyrolysis.

Abstract: One or more polymeric hollow fiber membranes are pyrolyzed to form one or more hollow fiber CMS membranes by directing a flow of pyrolysis gas through a polymeric membrane cartridge (including a porous center tube around which one or more green, polymeric, hollow fiber membranes is arranged) or a bundle of polymeric membranes (including a plurality of green, polymeric hollow fiber membranes oriented so that their ends are disposed with ends of the bundle) in a direction perpendicular to a length direction of the cartridge or bundle in order to sweep away off-gases that are formed during pyrolysis.

Abstract: One or more polymeric hollow fiber membranes are pyrolyzed to form one or more hollow fiber CMS membranes by directing a flow of pyrolysis gas through a bundle of polymeric membranes (including a plurality of green, polymeric hollow fiber membranes oriented so that their ends are disposed with ends of the bundle) in a direction perpendicular to a length direction of the bundle in order to sweep away off-gases that are formed during pyrolysis.

Abstract: Metallopolyimide precursor fibers for aging-resistant carbon molecular sieve hollow fiber membranes having enhanced selectivity include transition metal cations complexed with electronegative regions of a polyimide. CMS membranes are made by pyrolyzing the metallopolyimide precursor fibers. The cations are introduced by including, in the bore fluid used to extrude the fibers, either a salt of the transition metal and an inorganic anion or a transition metal/organic ligand complex.

Abstract: A carbon molecular sieve (CMS) membrane is made by pyrolyzing a polymeric precursor membrane in a pyrolysis atmosphere containing a sulfur-containing compound.

Abstract: A zeolite enhanced carbon molecular sieve (CMS) membrane is made by forming a precursor membrane from a matrix of polymer and zeolite particles and pyrolyzing the precursor membrane.

Abstract: H2S is removed from a feed gas by a gas separation membrane including a separation layer that is made of a blend of P84 and Matrimid.

Abstract: A carbon molecular sieve (CMS) membrane is made by pyrolyzing a polymeric precursor membrane in a pyrolysis atmosphere containing a sulfur-containing compound.

Abstract: H2S is removed from a feed gas by a gas separation membrane including a separation layer that is made of a blend of P84 and Matrimid.

Abstract: A carbon molecular sieve (CMS) membrane is made by pyrolyzing, to a peak pyrolysis temperature TP, a hollow fiber membrane having a polymeric sheath surrounding a polymeric core, anti-substructure collapse particles present in pores formed in the polymeric core help prevent collapse of pores formed in the hollow fiber membrane before pyrolysis. The anti-substructure collapse particles are made of a material or materials that either: i) have a glass transition temperature TG higher than TP, ii) have a melting point higher than TP, or ii) are completely thermally decomposed during said pyrolysis step at a temperature less than TP. The anti-substructure collapse particles are not soluble in a solvent used for dissolution of the polymeric material of the core.

Abstract: A composite hollow ceramic fiber includes a porous hollow core supporting a thin, dense sheath. The non-gas-tight core comprises a first ceramic compound and an interconnecting network of pores. The gas-tight sheath comprises a second ceramic compound. The fiber is made by extruding first and second suspensions of the first and second ceramic compounds in polymeric binders and solvent from a spinnerette and coagulating the nascent hollow fiber to effect phase inversion of the polymeric binders. The resultant green fiber is sintered in a two step process. First, the binder is burned off. Second, the sheath is densified and the second ceramic compound is sinter without fully sintering the first ceramic compound. The first ceramic compound has a melting point higher than that of the second ceramic compound.

Abstract: A composite hollow ceramic fiber includes a porous hollow core supporting a thin, dense sheath. The non-gas-tight core comprises a first ceramic material and an interconnecting network of pores. The gas-tight sheath comprises a second ceramic material. The fiber is made by extruding core and sheath suspensions from a spinnerette. The core suspension includes particles of the first ceramic material, a polymeric binder, a solvent, and a pore former material insoluble in the solvent. The sheath suspension includes particles of the second ceramic material, a polymeric binder and a solvent. The nascent hollow fiber is coagulated in a coagulant bath to effect phase inversion of the polymeric binders. The resultant green fiber is sintered in a two step process. First, the binders and pore former material are burned off. Second, the sheath is densified and the second ceramic material is sintered without fully sintering the core.

Abstract: A composite hollow ceramic fiber includes a porous hollow core supporting a thin, dense sheath. The non-gas-tight core comprises a first ceramic material and an interconnecting network of pores. The gas-tight sheath comprises a second ceramic material. The fiber is made by extruding core and sheath suspensions from a spinnerette. The core suspension includes particles of the first ceramic material, a polymeric binder, a solvent, and a pore former material insoluble in the solvent. The sheath suspension includes particles of the second ceramic material, a polymeric binder and a solvent. The nascent hollow fiber is coagulated in a coagulant bath to effect phase inversion of the polymeric binders. The resultant green fiber is sintered in a two step process. First, the binders and pore former material are burned off. Second, the sheath is densified and the second ceramic material is sintered without fully sintering the core.

Abstract: A composite hollow ceramic fiber includes a porous hollow core supporting a thin, dense sheath. The non-gas-tight core comprises a first ceramic compound and an interconnecting network of pores. The gas-tight sheath comprises a second ceramic compound. The fiber is made by extruding first and second suspensions of the first and second ceramic compounds in polymeric binders and solvent from a spinnerette and coagulating the nascent hollow fiber to effect phase inversion of the polymeric binders. The resultant green fiber is sintered in a two step process. First, the binder is burned off. Second, the sheath is densified and the second ceramic compound is sinter without fully sintering the first ceramic compound. The first ceramic compound has a melting point higher than that of the second ceramic compound.

Abstract: A membrane for fluid separation made of a blend of at least a polyimide polymer and a polyimidazole polymer.

Abstract: A membrane for fluid separation made of a blend of at least a polyimide polymer and a polyimidazole polymer.

Abstract: Mixed matrix composite (MMC) membranes with minimal macrovoids and defects are provided by the current invention. MMC Membranes are needed that have minimal macrovoids and defects, provide consistent and good selectivity and permeability performance, provide the mechanical strength required to withstand high membrane differential pressures, and exhibit sufficient flexibility and can easily be formed into desirable membrane forms. MMC Membranes made from a spinning dope that is stabilized with an electrostabilizing additive, particularly an acid additive, results in membranes, particularly hollow fiber membranes that have minimal macrovoids and defects. Thus, membranes of the current invention are particularly suitable for high trans-membrane pressure applications, particularly for separating oxygen/nitrogen, hydrogen/hydrocarbon, and carbon dioxide/hydrocarbon components of a stream.